Weight Training Apparatus and Method

ABSTRACT

A weight training apparatus includes a track rotatably connected to a frame for rotation about a first axis to define a first moment arm. A weight is carried by the track at preselected positions for providing torque. A movement arm is pivotally connected to the frame to define a second moment arm. A coupling between the movement arm and the track causes a rotating of the track in response to a rotation of the movement arm. An angular movement of the second moment arm through a second arc length results in an angular movement of the first moment arm through a first arc length, wherein the second arc length is greater than the first arc length for all rotations of the movement arm and the track. The weight thus moves more slowly than the resistance arm.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication Ser. No. 60/826,395 filed Sep. 21, 2006, the disclosure ofwhich is hereby incorporated herein in its entirety by reference.

FIELD OF THE INVENTION

The present invention generally relates to the field of exercisemachines, and more particularly to resistance and weight trainingexercise machines and related methods.

BACKGROUND OF THE INVENTION

A traditional weight machine generally includes a stack of weight blocksarranged in a vertical array and an engagement member to select aparticular block lifts that block and all upper blocks. The use of aweight stack provides a relatively easy method to change the resistancefor a particular exercise or a particular subject. However, the weightstack produces high frictional losses due to the required tracks andguide rods on either side of the blocks to control the movement of theselected blocks and ensure they do not become misaligned or disengaged.Most of the effort in friction reduction involves using lower frictionbearing materials on the weight blocks starting with metal plane bearingmaterial, plastic bearing material up to the low friction linear ballbearings. However, the high expense of linear ball bearings used foreach weight block has resulted in few manufacturers migrating from thehigher friction plane bearing methods. The present invention is directedto a need in the art to develop a weight resistance source for weighttraining machines providing reduced frictional losses while minimizingthe associated expense.

SUMMARY OF INVENTION

In keeping with the teachings of the present invention, a weighttraining apparatus may comprise a track rotatably connected to a framefor rotation of the track about a first axis. A resistance block may becarried by the track at a preselected position for providing apreselected torque thereto. A movement arm may be pivotally connected tothe frame for rotation about a second axis. The movement arm includes auser engagement portion for applying a resistive force to the movementarm. One embodiment may include a resistance arm for use as the userengagement portion. The resistance block and the track may be defined asforming a resistance block assembly having a center of gravity. Acoupling between the movement arm and the assembly causes a rotating ofthe track about the first axis in response to a rotation of the movementarm about the second axis, wherein an angular movement of the center ofgravity of the resistance block assembly through a first arc lengthresults from an angular movement of the user engagement portion througha second arc length, and wherein the second arc length is greater thanthe first arc length for all rotations of the movement arm and thetrack. The center of gravity of the assembly thus desirably moves moreslowly than the user contact portion.

Embodiments of the invention may include a keeper securing theresistance block to the track at the preselected position, wherein thekeeper comprises drive means operable with the resistance block formovement thereof. The resistance block may be moved from one preselectedposition to another for one fixed weight training to another, or may bemoved within a given weight training. By way of example the resistancefelt by a user operating the movement arm may react to a first torqueprovided by the resistance block assembly during an eccentric movementand to yet another during a concentric movement. The drive means maycomprise a threaded shaft, and wherein rotation of the shaft results ina linear movement of the resistance block along the track. Yet further,the drive means may comprise a crank for manually rotating the shaft ora drive motor for rotating the shaft.

In one embodiment, the resistance block is carried by the track so as todistribute its weight such that a center of gravity of the resistanceblock is generally aligned with a longitudinal axis of movement of theresistance block along the track. Embodiments may also include theresistance block having a plurality of weight blocks. The resistanceblock may be moved to locations along the track so as to providepositive and negative torque to the track. Yet further, a wheel assemblymay be employed with the resistance block and the track for ease insliding the resistance along the track from position to alternateposition.

For embodiments of the invention, the coupling may comprises resistancemodulating means for modifying a resistance felt by the resistance armat various locations within the second arc length for a fixedpreselected position of the resistance block on the track. By way ofexample, the resistance modulating means may comprise a cam, a rod, abelt, or a combination thereof. The fixed link may comprise a lift barfixedly attached to the track, wherein the lift bar includes opposingplates in spaced relation for permitting the resistance block to passtherebetween. The lift bar may further include a link bar providing anattachment point for the coupling. Alternatively, the fixed link may bepivotally attached to the track at a third axis.

The movement arm may further comprise adjustable means for slidablemovement of the resistance arm toward and away from the second axis ofrotation, thus allowing a modification to the length of the secondmoment arm.

A seat assembly may be connected to the frame and may comprise a basesupport and a back support.

BRIEF DESCRIPTION OF DRAWINGS

Features and benefits of the present invention will become apparent asthe description proceeds when taken in conjunction with the accompanyingdrawings and photos in which:

FIGS. 1 and 2 are front left and front right perspective views,respectively, of one embodiment of a weight training apparatus inkeeping with the teachings of the present invention, the apparatusillustrated in one starting position;

FIG. 3 is a elevation view of the embodiment of FIG. 1;

FIG. 4 is a perspective view of the embodiment of FIG. 1 illustratingthe apparatus in a weight lifting position;

FIG. 5 is a side view of the embodiment in FIG. 4;

FIG. 6 is a partial perspective view of a weight module portion of theembodiment of FIG. 1;

FIG. 7 is a top plan view of a weight module portion of the embodimentof FIG. 1;

FIG. 8 is a side view of the weight module portion of FIG. 7;

FIG. 9 is a rear view of the weight module of FIG. 7;

FIG. 10 is a perspective view of the weight module of FIG. 6illustrating a resistance block in an alternate position along a track;

FIG. 10A is a perspective view of an alternate embodiment of a weightmodule;

FIG. 11 is a partial perspective view including a track and weight blockoperable along the track using wheels;

FIG. 12 is a front right perspective of a alternate embodiment of aweight training apparatus in keeping with the teachings of the presentinvention;

FIG. 13 is a rear perspective view of the embodiment of FIG. 12; and

FIG. 14 is a side view of the embodiment of FIG. 12.

DETAILED DESCRIPTION OF EMBODIMENTS

The present invention will now be described more fully hereinafter withreference to the accompanying drawings, in which embodiments of theinvention are shown. This invention may, however, be embodied in manydifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art. Likenumbers refer to like elements throughout, and prime notation is used toindicate similar elements in alternate embodiments.

Referring initially to FIGS. 1-3, one embodiment of the invention mayinclude a weight training apparatus 10 having a track 12 rotatablyconnected to a frame 14 at a first fulcrum 16 for rotation of the trackabout a first axis 18. A resistance block 20 is carried by the track 12.The resistance block 20 and the track 12 form a resistance blockassembly 22 having a center of gravity 23. As will be clear to those ofordinary skill in the art, the center of gravity will generally belocated within the block but is herein illustrated as viewed from a sideor top for illustration purposes. A distance from the center of gravity23 to the first axis 18 defines a first moment arm 24. The resistanceblock 20 may be located at a preselected position 26 for providing apreselected torque to the track. As will be further detailed, variouspositions along the track 12 are available for placement of theresistance block 20 depending upon the weight training exercise desiredand thus torque to be provided. For the embodiment herein described byway of example, a movement arm 28 pivotally connected to the frame 14 ata second fulcrum 30 for rotation of the movement arm about a second axis32. For the embodiment herein described by way of example with referenceto FIG. 1, the movement arm 28 includes a resistance arm 34 at a userengagement portion of the movement arm. A distance from the resistancearm 34 to the second axis 32 defines a second moment arm 36. As is knownin the art, such a resistance arm 34 may be padded for providing comfortto a user operating the apparatus 10. As will be further addressed laterin this section, the movement arm 28 may not be carried by the frame 14and may be attached to other assemblies forming a part of alternateembodiments of the weight training apparatus 10.

With continued reference to FIGS. 1-3, and to FIGS. 4 and 5, a coupling38 between the movement arm 28 and a fixed link 13 attached to the track12 causes a rotating of the track about the first axis 18 in response toa rotation of the movement arm 28 about the second axis 32. An angularmovement 40 of the second moment arm 36 through a second arc length 42results in an angular movement 44 of the first moment arm 24 through afirst arc length 46, wherein the second arc length is greater than thefirst arc length for all rotations of the movement arm 28 and the track12. The resistance block 20 thus moves more slowly than the resistancearm 34.

As illustrated herein by way of example with reference to FIGS. 6 and 7,the apparatus 10 may include a keeper 48 securing the resistance block20 to the track 12 at the preselected position 26. The keeper 48includes a drive mechanism 50 for moving the resistance block 20 alongthe track 12. The drive mechanism 50 as herein described by way ofexample, includes a threaded shaft 52. By rotating the shaft 52, thereis a linear movement 54 of the resistance block 20 along the track 12.As herein described, the drive mechanism 54 may comprise a crank 56A formanually rotating the shaft or a drive motor 56 for rotating the shaft52.

In one embodiment, and as illustrated with reference to FIGS. 8-9, theresistance block 20 is carried by the track 12 so as to distribute theweight of the resistance block uniformly above 58 and below 60 the track12 such that the center of gravity 13 of the resistance block assembly22 is generally aligned with a longitudinal axis 64 of the track 12,which for the embodiment illustrated herein by way of example isgenerally along the axis of the shaft 52. A plurality of weight blocks66 permits ease in distributing the weight. As illustrated withreference to FIG. 10, the resistance block 20 may be moved to alternatelocations 68 along the track 12 so as to provide positive and negativetorque to the track, depending upon the location of the center ofgravity 23 in relation to the first axis 18, by way of example. Yetfurther, wheels 70 may be used with the resistance block 20 and thetrack 12 for ease in moving the resistance along the track from positionto alternate position, as illustrated with reference to FIG. 11.

For alternate embodiments of the invention, the coupling 38 may comprisea resistance modulator 72 for modifying a resistance felt by theresistance arm 34 at various locations within the second arc length 42for a fixed preselected position of the resistance block 20 on the track12, or at varying locations along the track for operations where theresistance block is moving as a result of the motor drive 56 continuallyor intermittently relocating the resistance block during a desirableexercise. By way of example, the resistance modulator may comprise a cam74 (as illustrated with reference to FIGS. 12-14), a rod 76 (asillustrated with reference again to FIG. 1), a belt 78 (as illustratedwith reference to FIG. 4), or a combination thereof. With continuedreference to FIGS. 1, 6 and 8, the fixed link 13 may comprise a lift bar80 fixedly attached to the track 12, wherein the lift bar includesopposing plates 82, 84 in spaced relation to each other or dimensionedfor permitting the resistance block 20 to pass therebetween. The liftbar 80 may further include a link bar 86 providing an attachment pointfor a strap 88 forming a portion of the coupling 38. Alternatively, thefixed link 13, while fixed at a location on the track 12, may bepivotally attached to the track at a third axis 90, as illustrated withreference to FIG. 1A.

With reference again to FIGS. 12-14, an alternate embodiment of theinvention may be described with reference to the apparatus 11, wherein alinkage 92 connects the movement arm 28 to the coupling 38. The linkage92, for one embodiment herein described by way of example, may comprisesa pulley assembly 94 rotatably connected to the frame 12 and a strap 96connected between the pulley assembly and the movement arm 28 foroperation of the coupling 38 through a movement of the movement arm. Asillustrated by way of further example with continued reference to FIGS.12-14, the movement arm 28 may be carried by a seat assembly 98. Asillustrated with reference again to FIGS. 1 and 2, the movement arm 28may further comprise adjustable means 100 for slidable movement of theresistance arm toward and away from the second axis 32 of rotation, thusallowing a modification to the length of the second moment arm 36. Theadjustable means 100 may also include an adjustment to an angle of themovement arm 28, as may be desired.

As illustrated with reference again to FIGS. 1, 2, 12 and 13, the seatassembly 98 may comprise a base support 102 and a back support 104.

By way of further example, and with reference again to FIGS. 6-8, oneembodiment of the apparatus 10 may include the track 12 constructed tohave opposing side plates 12 a, 12 b connected at their respective endsby two end plates 12 c, 12 d. An outside plate 12 e may be connected atan outside face of the end plate 12 c. The threaded shaft 52 ispositioned between the side plates 12 a, 12 b and may extend beyond theoutside plate 12 e, terminating at an extension 52 a of the threadedshaft 52. As above described, the resistance block 20 may include aplurality of weight blocks 66 wherein a threaded nut 20 a receives thethreaded shaft 52. As illustrated with reference to FIGS. 10A and 11,the resistance block 20 may further include a plurality of axes 70 a forrotatably securing the wheels 70 on opposite sides of the resistanceblock 20 adjacent the respective side plates 12 a, 12 b. One set of thewheels 70 is used for contacting opposite top surfaces of the sideplates 12 a, 12 b, while another set of wheels is used for contactingopposite lower surfaces of the side plates. As above described, theresistance block 20 is thus supported for being fixed and rolled backand forth within the track 12 on the wheels 70. As illustrated withreference to FIG. 7, the resistance block 20 may optionally include apair of side grooves 12 f, 12 g, along the length of their sidesadjacent the side plates 12 a, 12 b for slidably receiving respectiveside guide rods 52 b, 52 c each extending from the opposing end plates12 c, 12 d. The resistance block 20 may therefore be further supportedand slide back and forth within the track 12 on the side guide rods 52b, 52 c.

With reference again to FIG. 1, the first fulcrum 16 extends outwardfrom either side plate 12 a, 12 b for securing the track 12 to a weighttraining machine such as the apparatus 10 and 11 herein described by wayof example.

An attachment to the track may be a flexible tensile member such thestrap 88 above described or may be a chain or rigid member to transmit aforce to the movement arm 28. The threaded shaft 52 secures theresistance block 20 at the preselected position 26. To adjust theposition of the resistance block 20 along the track 12, the threadedshaft 52 is rotated and the resistance block 20 is moved along the sideplates to a desired location.

With reference again to FIGS. 1 and 2, and by way of continued examplefor one construction of the apparatus 10, to connect and secure thetrack 12, the first fulcrum 16 comprises bearings 16 a. The fulcrum axis18 is aligned and inserted into the bearings 16 a carried by opposingframe bars 14 a, 14 b of the frame 14, thus securing the track 12 to theframe 14. The movement arm 28 of the apparatus 10, 11 (alternate weighttraining machines) may be coupled to an axle rotating about the axis 32.

The resistance modulator 72 may change the resistance so that the useris presented with enough resistance to be challenged but not enoughresistive force to overcome to prevent completion of a desired exercisemovement. The seated leg extension machine illustrated as the apparatus10 may have a resistance profile that increases from the beginning ofthe exercise, progresses to a maximum when the knee joint forms anapproximate 90 degree angle, and decreases to below the startingresistance at the end of the exercise. As above described and asillustrated by way of example with reference to FIGS. 12-14 for theapparatus 11, the track 12 and resistance block 24 structure hereindescribed may be secured to any weight training machine capable ofhousing the track and resistance block while accommodating its rotationcycle and coupling the movement arm 28 or its equivalent to the track12.

By way of example with regard to use or operation of the apparatus 10,11, in selecting a desired level of resistance, a minimum level ofresistance may be attained by positioning the resistance block 20 at thezero position, in which the center of mass of the track and resistanceblock generally coincides with the first fulcrum 16 (see FIG. 10 by wayof example). At the zero position, the center of mass does not changeheight relative to the frame over the repetition cycle, and thus doesnot contribute any increase in potential energy to an increase in thelevel of resistance realized by the user. As will be clear to thoseskilled in the art, now having the benefit of the teachings of thepresent invention, a maximum level of resistance may be attained bypositioning the resistance block at a maximum position, in which thecenter of mass is at the farthest position from the first fulcrum 16(see FIG. 6 by way of example). At the maximum position, the center ofmass experiences a maximum change in height over the repetition cycle,corresponding to a maximum increase in potential energy corresponding toa maximum increase in the level of resistance. As above described, theshaft 52 may be used to select a continuous level of resistance levelsbetween the zero position and maximum position, through removablysecuring and positioning the resistance block 20 along the track 12. Asillustrated with reference again to FIG. 1, a repetition cycle may havethe track 12 move from being generally horizontal prior to the userimposing any force on the resistance arm 34 to a large angle asillustrated with reference again to FIG. 4.

By way of example with regard to a weight training program, the trackcarrying the resistance block accepts work from the user to rotateupward in a gravitational field, increasing the potential energy of theweight provided and thus the resistance provided to the user. On thereturn movement or eccentric portion of an exercise, the potentialenergy is returned to the user who expends work to lower the weightunder control. Minimal frictional loss occurs during the movement of thetrack during a repetition cycle, as the weight only generates frictionat the first fulcrum 16, which may be anti-friction ball bearings ofappropriate size, for example. Such a weight resistance structureproduces noticeably less friction than multiple plane bearings slidingalong twin guide rods. Moreover, the leg extension machine of apparatus10 illustrated in FIG. 1, for example, includes one resistance arm 34interfaced with the movement arm 28 such that a desired resistanceprofile is achieved with only one idler pulley 38 a in the connectionfrom the movement arm 28 to the track 12. The relatively small number ofdrive train elements reduces frictional loss during the repetitioncycle.

The torque that exercisers can transmit to an arm or pad of a machinevaries with the movement of limb within the range of motion. The musclesthat extend the leg at the knee (quadriceps) are able to produce 65% to85% of the peak torque that occurs when the Tibia is approximately atright angles to the Femur. From this peak, the produced torque smoothlydecreases to about 30% to 50% of the peak in the fully extendedposition. The resistance modulator 72 such as the cam and belt, cam andfollower or linkage system as earlier described, may be such so as toprovide a resistance to the user that matches the torque that the usercan produce at a particular point in the range of motion. This meansthat the resistance provided by the apparatus 10, 11 is lower where theuser produces less torque and is proportionally greater where the useris strongest. The torque that users can produce at various angles withinthe range of movement can be measured and averaged to come up with amachine resistance profile. These profiles vary for each muscle groupand limb exercised as well as for the position of the users' body duringthe exercise. For instance, the torque and the range of motion of thehamstrings vary slightly when the hips and trunk are flexed or straight.

The resistance presented by a weight training machine must be less thanthe torque that the user can supply or the user will not be able tocomplete the repetition. In order to stimulate muscle growth however,the resistance should be challenging enough so that the body tends torebuild. Ideally then, the resistance should be just slightly lower thanthe user's torque capacity at each angle in the range. This will ensurethat the exercise can be completed through the full range of motion andthe effort will be close to the maximum level that the user can apply atthe strongest areas as well as the weaker angles.

One basis for designing a resistance modulation profile includes the lawof conservation of energy. For weight training machines, the mechanicalwork input by the user equals the change in potential energy of theweight mass plus the friction plus kinetic energy. All other energysources and sinks are neglected as inconsequential. In order for theresistance profile of the machine to be accurately presented to theuser, the friction and kinetic energy component of the machine should bereduced to the greatest practical extent, as is the case from theembodiment of the invention herein described. The track and resistanceblock forming a resistance module based on a pivoting lever isinherently low in friction in comparison to weight stacks with guiderods, typically seen in the art. Keeping the distance traveled by themodule center of mass less than the distance traveled by the engagingbody part reduces the velocity of the resistance mass. The low velocityreduces kinetic energy content of the movement which is related by ½mv².The m is mass and velocity is v. Because the friction and kineticcomponents of the repetition are reduced, the work added by the usermore closely follows the resistance profile designed into the machine.

When the displacement of the center of mass of the resistance moduleover the repetition cycle is less than the resistance arm, by way ofexample, the velocity or acceleration is correspondingly less than thatof the resistance pad and may not contribute large kinetic energyeffects in addition to the inherent resistance profile. The resistancemodule may include the center of mass of the resistance modulepositioned along the side bars of the track such as at the maximumposition, for example, and displacing a distance less than theresistance arm over the repetition cycle. Thus, for all resistancelevels, the kinetic energy effects may be minimized. A less desirableconfiguration may include a small mass displacing a larger distance thanthe resistance arm, resulting in a higher travel velocity and highkinetic energy effects. The typical design for weight training systemshave the distance traveled by the engagement pad or handle equal to orless than the distance traveled by the mass center of the resistanceweight. The resistance module has the center of mass traveling less thanthe distance of the engagement handles and pads. Consider a distancetraveled by the resistance arm or handles of an alternate apparatus, byway of example, to be Dh and the distance of travel of the weight modulecenter of mass to be Dwt. The resistance module will follow the equationDh/Dwt<1.

A repetition cycle may involve a concentric portion where the tension ofthe muscle and the direction of movement are the same, and an eccentricportion where the tension of the muscles and the direction of movementof the muscles are in opposite directions. During a biceps curl, forexample, the concentric portion of the exercise may be lifting theweight and the eccentric portion may be lowering the weight.

The eccentric portion of a repetition in current weight trainingmachines may involve less resistance due to frictional loss of themachines. However, the frictional loss of such machines may add to theresistance during the concentric portion of the repetition cycle. Thus,the frictional loss may add to the concentric resistance when liftingthe weight and subtract from the eccentric resistance when lowering theweight. Thus, the eccentric portion of the repetition cycle may be lesseffective than the concentric portion.

The resistance module may provide a consistent level of resistancethroughout the repetition cycle by supplying additional resistanceduring the eccentric portion to offset frictional loss. Increasing theresistance during the eccentric portion may be accomplished throughmoving the resistance block 20 away from the first fulcrum 16 when theuser begins the lowering part of the exercise. By lengthening thedistance the resistance block 20 can travel by 20%, for example, ordecreasing the maximum concentric travel by 20%, for example, themuscles may encounter greater resistance in the eccentric portions ofthe repetition cycle. Upon the user beginning the concentric portion,the resistance block 20 may have returned to its initial position on thetrack 12.

The ability of the user to generate torque at a particular limb anglemay be used to generate the resistance curve that is designed into thecam, lever or other resistance modulator 72 providing a modulatingeffect. The match between the programmed resistance curve and the user'sability to generate torque should be similar to accomplish an efficientexercise. If the match is not sufficiently similar, the user may not beable to exercise in a portion of the repetition range, nor besufficiently challenged in a portion of the repetition range.

The resistance block 20, as above described, may be moved along thetrack 12 using the drive motor 56 controlled to adjust the position ofthe resistance block 20 to a particular position at the beginning of anexercise when a minimum amount of control is used. By increasing theamount of control, the motor may move the resistance block to theendpoints of the exercise to increase the eccentric phase of theexercise and decrease the concentric phase.

Consider a workout with increased eccentric phase resistance to includethe following steps:

1. Set eccentric phase resistance level (may enter on a keypad 106forming a portion of a controller 108, as illustrated with referenceagain to FIG. 1, by way of example)

2. Set concentric phase resistance level (enter on keypad)

3. Set range of motion (complete repetition with ½ concentricresistance, end points recorded)

4. Machine sets concentric value (moves weight block to position)

5. Machine signals ready to start (screen text, audio cue)

6. Start exercise

7. At the end of the range, pause under load for 2 seconds (weight movesto eccentric value)

8. Lower weight under control

9. Immediately begin to lift weight (weight moves to concentric value)

10. Repeat steps 6-9 (machine records repetition and time of exercise)

11. Exercise recording and weight changes stop when the range decreasesto 80%

The eccentric and concentric resistance levels can also be set byentering either the concentric level or the eccentric level and enteringthe percentage increase of the eccentric over the concentric resistancelevels. An increase of 2% to 5% would be equivalent to completelyremoving friction out of the exercise machine. In this case the additionof machine friction to the concentric movement and the subtraction ofthe machine friction from the eccentric movement would be offset exactlyby the additional resistance for the eccentric movement. The eccentricstrength level is commonly thought to be 40% greater than the concentricstrength level. This could be the default setting for the machine whenusing the increased eccentric mode. Otherwise the percentage of increasewould be entered by the user or trainer.

Consider a maximum effort workout to comprise the following steps:

1. Set range of motion with moderate speed full repetition (speed 3-8second lift, 2-5 second pause-6-10 second lower and end points recorded)

2. Set concentric resistance to 1 RM or slightly lower (1 Repetitionmaximum or 5% to 10% lower)

3. Machine sets concentric value (moves weight block to position)

4. Machine signals ready to start (screen text, audio cue)

5. Start exercise

6. Machine records complete repetitions that are full range within80%-90%.

7. Machine lowers weight until the range is within 80%-90% of theoriginal

8. When concentric values are lower than the 1 RM by 20%40%, theincreased eccentric resistance workout steps begin steps 8-9-10

9. When either concentric or eccentric phases are below 80%-90% of therange, the weight lowers until the range is restored.

10. Machine records full range repetitions and time of the exercise

11. Workout ends at selected repetition, time or percentage of startingweight.

An additional variation of a standard workout keeps the same resistancesetting for the concentric and eccentric phases. This variation issimilar to having a trainer or spotter assist the exerciser complete thelast several repetitions.

A concentric workout with maximum effort finish may comprise:

1. Set concentric phase resistance level

2. Set range of motion

3. Machine sets concentric value (moves weight block to position)

4. Machine signals ready to start (screen text, audio cue)

5. Start exercise

6. Pause at the end of the range

7. Lower weight under control

8. Immediately begin to lift weight

9. Repeat steps 6-9 (machine records repetition and time of exercise)

10. When range of motion falls below 80%-90% of the recorder ROM, theweight reduces until the ROM is restored.

11. Reduction of weight continues for either a set number of additionalrepetitions or until the weight is a certain percentage of the originalweight setting.

The increased eccentric phase workout can have the maximum effort finishas well. Consider the following.

1. Set eccentric phase resistance level

2. Set concentric phase resistance level

3. Set range of motion

4. Machine sets concentric value (moves weight block to position)

5. Machine signals ready to start (screen text, audio cue)

6. Start exercise

7. At the end of the range, pause under load for 2 seconds (weight movesto eccentric value)

8. Lower weight under control

9. Immediately begin to lift weight (weight moves to concentric value)

10. Repeat steps 6-9 (machine records repetition and time of exercise)

11. When either concentric or eccentric phases are below 80%-90% of therange, the weight lowers until the range is restored

12. Reduction of weight continues for either a set number of additionalrepetitions or until the weight is a certain percentage of the originalweight setting

Yet further, the controller 108 may include a full servo feedback systemmay be used, for example, to control the position and velocity of theresistance block and enable the machine to superimpose a correction tothe “hardwired” resistance curve that would enable an ideal matchbetween the subject's ability and the machine's resistance. Such ahybrid electro-mechanical machine's primary resistance may be suppliedby the resistance block being lifted and lowered while theservo-mechanics may shape the resistance to the user by making smallchange to the design in average resistance provided by the cam orlevers. This system may differ from pure electronic exercise devicesthat use servo motors for resistance. The systems for electronicresistance machines may be very fast, accurate and generate greatamounts of torque.

In an exemplary embodiment, a hybrid electro-mechanical system may onlyneed the power and control to move a 100-400 pound mass along a lowfriction linear guide rod rather than having to generate up to 1000 to1500 ft-lb of work in less than 90 degrees of movement arm rotation.

Many modifications and other embodiments of the invention will come tothe mind of one skilled in the art having the benefit of the teachingspresented in the foregoing descriptions and the associated drawings andphotos. Therefore, it is to be understood that the invention is not tobe limited to the specific embodiments disclosed, and that modificationsand alternate embodiments are intended to be included within the scopeof the claims supported by this specification.

1. A weight training apparatus comprising: a frame; a track rotatablyconnected to the frame and pivotal about a first axis, a resistanceblock carried by the track at a relocatable preselected position alongthe track, wherein the resistance block and the track form a resistanceblock assembly having a center of gravity; a movement arm pivotal abouta second axis, the movement arm having a user engagement portion forapplying a force to the movement arm; a coupling connecting the movementarm to the resistance block assembly for rotating the track about thefirst axis in response to rotation of the movement arm about the secondaxis, wherein an angular movement of the center of gravity of theresistance block assembly through a first arc length results from anangular movement of the user engagement portion through a second arclength, and wherein the second arc length is greater than the first arclength for all rotations of the movement arm and the track, the centerof gravity of the resistance block assembly thus moving more slowly thanthe user engagement portion.
 2. An apparatus according to claim 1,further comprising a fixed link fixedly attached to the track, whereinthe coupling is connected to the fixed link.
 3. An apparatus accordingto claim 1, further comprising a keeper securing the resistance block tothe track at the preselected position.
 4. An apparatus according toclaim 2, wherein the keeper comprises a drive mechanism operable withthe resistance block for movement thereof.
 5. An apparatus according toclaim 4, wherein the drive mechanism comprises a threaded shaft, andwherein rotation of the shaft results in a linear movement of theresistance block along the track.
 6. An apparatus according to claim 1,wherein the resistance block is carried by the track so as to distributeits weight such that the center of gravity of the resistance blockassembly is generally aligned with a longitudinal axis of the track. 7.An apparatus according to claim 1, wherein the resistance blockcomprises a plurality of weight blocks.
 8. An apparatus according toclaim 1, wherein the resistance block is moveable to locations along thetrack from one side of the first axis to an opposing side thereof forproviding positive and negative torque thereto.
 9. An apparatusaccording to claim 1, further comprising a wheel assembly operablebetween the resistance block and the track, the wheel assembly enhancinga slidable movement of the resistance block along the track from thepreselected position to a second preselected position.
 10. An apparatusaccording to claim 1, wherein the coupling comprises a resistancemodulator for modifying a resistance felt by the user engagement portionat various locations within the second arc length for a fixedpreselected position of the resistance block on the track.
 11. Anapparatus according to claim 10, wherein the resistance modulatorcomprises at least one of a cam, a rod, and a belt.
 12. An apparatusaccording to claim 1, wherein the movement arm comprises adjustablemeans for slidable movement of the resistance arm toward and away fromthe second axis of rotation, thus allowing a length modification to thesecond moment arm.
 13. An apparatus according to claim 1, wherein themovement arm is pivotally connected to the frame, and wherein the userengagement portion includes a resistance arm attached generallyperpendicular to the movement arm.
 14. An apparatus according to claim1, further comprising a linkage connecting the movement arm to thecoupling.
 15. An apparatus according to claim 14, wherein the linkagecomprises a pulley assembly rotatably connected to the frame and a strapconnected to the movement arm for operation of the coupling therewith.16. An apparatus according to claim 1, further comprising a seatassembly operable with the frame, wherein the seat assembly comprises abase support and a back support.
 17. An apparatus according to claim 16,wherein the movement arm is carried by the seat assembly.
 18. Anapparatus according to claim 2, wherein the fixed link comprises a liftbar fixedly attached to the track, wherein the lift bar includesopposing plates in spaced relation and dimensioned for permitting theresistance block to pass therebetween, the lift bar further including alink bar providing an attachment point for the coupling.
 19. Anapparatus according to claim 18, wherein the fixed link is pivotallyattached to the track at a third axis.
 20. A weight training apparatuscomprising: a frame a track rotatably connected to the frame; aresistance block carried by the track at a preselected position thereon;a movement arm having a user engagement portion for applying a forcethereto; and a coupling operably between the movement arm and the trackfor rotating the track in response to a movement of the movement arm,wherein a movement of the movement arm through a first length dimensionresults in an angular movement of the track through a second lengthdimension, and wherein the first length dimension is greater than thesecond length for all movements of the movement arm and the track, theresistance block thus moving more slowly than the movement arm.
 21. Anapparatus according to claim 20, wherein the second length dimensionincludes an arc length dimension.
 22. An apparatus according to claim20, further comprising a keeper securing the resistance block to thetrack at the preselected position.
 23. An apparatus according to claim22, wherein the keeper comprises a drive mechanism operable with theresistance block for movement of the resistance block along the track.24. An apparatus according to claim 20, wherein the resistance block iscarried by the track so as to distribute its weight such that a centerof gravity of the resistance block is generally aligned with alongitudinal axis of the track.
 25. An apparatus according to claim 20,wherein the resistance block is moveable to locations along the trackfor providing positive and negative torque thereto.
 26. An apparatusaccording to claim 25, the resistance block is moveable along the trackduring a period wherein the user engagement portion is applying theforce to the movement arm.
 27. An apparatus according to claim 20,wherein the coupling comprises a resistance modulator for modifying aresistance felt by the user engagement portion for a fixed preselectedposition of the resistance block on the track.